package com.tebon.ams.util;
import org.apache.commons.codec.binary.Base64;
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.security.MessageDigest;
import java.security.SecureRandom;
public class AESUtil {
/**
* 功能：生成AES秘钥并写入指定文件中
*
* @param filePath
* 文件夹绝对路径，必须是已存在文件
* @throws Exception
*/
public static void genAESKeyPair(String filePath) throws Exception {
// keySpec 生成对称密钥
KeyGenerator keyGenerator = KeyGenerator.getInstance("AES");
keyGenerator.init(128);
SecretKey secretKey = keyGenerator.generateKey();
SecretKeySpec keySpec = new SecretKeySpec(secretKey.getEncoded(), "AES");
try {
String publicKeyString = Base64.encodeBase64String(keySpec.getEncoded());
System.out.println(publicKeyString);
FileWriter pubfw = new FileWriter(filePath + "AESKey.key");
BufferedWriter pubbw = new BufferedWriter(pubfw);
pubbw.write(publicKeyString);
pubbw.flush();
pubbw.close();
pubfw.close();
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 获取签名
*
* @param data
* 要加签的数据
* @param MD5key
* 加签时使用的key
* @return 签名字符
* @throws Exception
*/
public static String getSignature(String data, String MD5key) throws Exception {
data = data + "|" + MD5key; // data与key
MessageDigest md = MessageDigest.getInstance("MD5");
byte[] b = md.digest(data.getBytes("UTF-8")); // md5签名
return Base64.encodeBase64String(b); // base64转码
};
/**
* AES加密
*
* @param plainTextData
* 要加密的数据
* @param key
* 加密时使用的key
* @return 返回加密后的数据
* @throws Exception
*/
public static String encryptAES(String plainTextData, String key) throws Exception {
// 密钥
KeyGenerator kgen = KeyGenerator.getInstance("AES");
SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
secureRandom.setSeed(key.getBytes());
kgen.init(128, secureRandom);
SecretKey skey = kgen.generateKey();
byte[] raw = skey.getEncoded();
SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
// 加密数据
Cipher cipher = Cipher.getInstance("AES");
cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
byte[] encryptedData = cipher.doFinal(plainTextData.getBytes("UTF-8"));
return Base64.encodeBase64String(encryptedData); // base64转码
}
/**
* AES解密
*
* @param encryptedData
* 要解密的数据
* @param key
* 解密使用的key
* @return 解密后的数据
* @throws Exception
*/
public static String decryptAES(String encryptedData, String key) throws Exception {
// 密钥
KeyGenerator kgen = KeyGenerator.getInstance("AES");
SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
secureRandom.setSeed(key.getBytes());
kgen.init(128, secureRandom);
SecretKey skey = kgen.generateKey()